Press



oct. 4, 1932, J, DEJRRY 1,880,874

PRESS Filed April l1. 1930 3 .Sheets-Shes?I l INvN-I-EIR:

' @CL 4s i932. J, BERRY 1,8874

PRESS Filed April 11. 195o 3 sheets-sheet 2 INvEN-l-DR:

0t.4, 1932. J, BERRY 1,880,874 l PREss` l Filed April 11, 1950 3Sheets-Sheet 5 EYWMNL Patented Oct. 4, 1932 PATENT-i :t

JASPER DERBY, on MEDFORD, MASSACHUSETTS, AssIGNon To ANDREW TnnknnsnN,or NEWTON, MASSACHUSETTS PRESS Application led .April 11, 1930. SerialN'o. 443,390.

.This invention relates to presses and is inV press wherein the closingmovement of the press elements is automatically controlled and limitedby the pressure exerted upon the work irrespective of the size andcharacter of the latter, and wherein said pressure is maintained afterthe stopping of the press, noty withstanding subsequent volumetricchanges in the work, to provide means for automatically stopping theopening movement of the press elements .whenthey have been separated bya predetermined Vbut 'variable amount, to provide means whereby the pre.determined pressure exerted upon the work can be conveniently adjustedand varied in accordance with the requirements, and to pro- Vvide meanswhereby the operation ofk the press can be manually,as well asautomatically, controlled. y

More particular objects of the present invention are toprovideanelectrical control for presses of this type, thereby greatlysimplifying the mechanism, and to provide means for automaticallystopping the movement of the-movable press element toward thecooperating element upon failure, for any reason, of said cooperatingelement to eXert its normal reaction to the pressure exerted by saidmovable element. Y

The foregoing and other objects of the invention, together with meanswhereby the latter may be carried into eiect, will best be understoodfrom the following description of a preferred embodiment thereofillustrated in the accompanying drawings, but it will also be understoodthat the particularconstruct-ion and adaptation described and shown havebeen chosen for purposes of exemplification merely, and that theinvention, as defined by the claims hereunto appended, may be otherwiseembodied'without `departure from the. spirit and scope thereof.

In said drawings:

Fig-1 is a front elevation of a press em-l bodying the invention, f

F ig. 2is a horizontal section taken substantially on the line 2-,-2 ofFig. 1,

Fig'. 8 is awiring diagram of the electrical connections, A

F ig. 4 is a detail,verticalsectional view of the electromagneticreversing switch.

Fig. 5 is a detail view of the solenoid brake.

Referring particularly to Figs. 1 and 2the relatively movable presselements comprise a bed l5 and a ram 16 which may carry suitablecomplementary dies 17 or other devices in accordance withY the natureofthe work to be performed by the press. The bed'15 is supported byfourparallel, upright posts or rods 18 to which it is secured in anysuitable manner, as by means of nuts 19 engaging threaded end portions19a on said posts. A The posts lor rods 18 'are guided for ver ticallongitudinal movement in suitable bearings 20 and'21 in the frame 14,the latter being` adapted -to receive the reduced portions 10 at thelower ends of said posts and constituting abutments upon which saidposts normallyV rest.

Surroundingthe postsor rods 18 below the bearings 2O are heavy coilsprings 22 interposed between ianges 23 formed on the frame and collars24 -in engagement with the threaded lower ends 25 of said posts andsecured Yin adjusted position thereon by set screws 12. The collars 24cooperate with the rods 18 whereby the springs 22 may be placed and heldunder a predetermined initial compression. l `With this arrangement itywill be seen vthat when the press elements approach one another, soasto'engage the work therebetween at opposite sides, the pressure of theram against the vwork and bed.`

will be transmitted to the springs`22 which willyield to permit movementof the bed and displacement of the posts to an extent determined by thepressure applied and consequent compression of the springs.

The ram 16is carried by a'double rack 27 guided in the frame 14 andengaged Aat opposite sides by two pairs of pinio'nsl 28 100 fast onparallel shafts 29 journalled in the frame and also having fast thereonintermeshing gears 30 connecting the pinions of each pair. One gear 30of each pair of pinions meshes with a pinion 31 fast on a shaft 32journalled in the frame and having fast thereon a gear 33. The gear33-meshes with a pinion 34 fast on a shaft 35 journalled in the frameand having fast thereon a gear 36. The gear 36 meshes with a pinion 37fast on a shaft 38 which is journalled in a gear casing 39 carried bythe frame. The

shaft 38 has fast thereon a worm gear 4.0V

which meshes with a worm'l on the *arma` ture shaft 4t2 of an electricmotor M suitably supported on the frame, said shaft 42 being likewisejournalled in the gear casing 39.

The motor M, which ispreferably an alternating current motor of thethree-phase type, is supplied 'with electrical energy from three feedlines L1,.L, and L3. (SeeFig. 3.)Y In accordance with the invention, theoperation ofthe motor is controlledto move the ram 16=in one directionto exert the predetermined' pressure upon the work and in a reversedirection to release the pressure and separate thel press elements.. Forthis pur# pose the passage of the current through the feed lines vto thevmotor is controlled by a magnetic reversing switch R'which throws themotor across the line.` l

The reversing switch R'(see Figs. 3 and 1)v is provided with twotriplepole, mag-` netically-operated contactors a and b' which are wiredas shown in Fig. 3.so that whenV one contactor is closed the motoroperates in one direction and when the other contactorisY closed themotor operates in-the reverse direction.l Each contactor. is closed byan operating coil 61v or 71 which is controlled by a separate circuitconnected with the feed lines, both circuits lbeing controlled by amanually operated, three-button control station C having an up switch80, a down switch 81and a stop switch 82. The up and down switches areof the momentary contact: type, being normally open while the stopswitch is normally closed. lEach circuit is further controlled bya limitswitch A or B- which is operated automatically to stop the motor andthus limit the movement ofthe ram in eitherdirection. The limit switchesare normally closed. y

The contactor-a (seewparticularly Figa) comprises lfixed and movablemembers, the latter beingpivotally mounted on the frame .112 ofthereversing switch,fand being provided with anarmature which cooperateswith the coil 61 when the latter is energized to close said contactor.An .electricinterlock e, operated Vby the contactora and'provided forthe purpose of'closing: its operating circuit, comprisesa movable member111 yieldlnglymounted A1n the movable member 'G5 of said contactor andfixedmembers 113. se-

cured to the frame 112. The contactor b likewise comprises fixed andmovable vmembers, the latter being pivotally mounted on the frame 112and being provided with an armature 114 which cooperates with the coil71 when the latter is energized to close said contactor. An electricinterlock y operated by the contactor b and provided for the purpose ofclosing itsopera-ting circuit comprises ammovable member- 11'5yieldingly mounted in the movable member of said contactor and Xedmembers 116 secured to the frame 112. The contactors are mechanicallyinterlocked by a bar 117 pivoted intermediate its ends to the frame 112,said ends beingV secured by links 118 to each of the Vmovable membersofsaid contactors. This. construction Aprevents both contactors beingclosed atthe same time. The contactors and the electric. interlocks arenormally open,

but when either contactor is closedlthe interlock forV completing itsoperating circuit is also closed whiletheother interlock is open, v

the closing ofl only vone cir#` A,wire 65, s top7 switch .82, wires66and l" 67, and out through line L3.

Thiscauses the operating coil 61 Vto-.be energized and the contactor ato be closed, which connects theV feed lines L1, L2 and-La with themotor as shown in Fig. 3, to drive it in a direction to move the ram 16forwardly, or upwardly, towards the bed of the press. As this contactoris closed, its inter-- lock c is closed, andthe current may now flowthrough line L2, wire 60, coil 61, wire 62, interlock e, wires. 68 and64, limit switch A, wirev65, stop switch 82,7wires 66 and 67 and lineLa, or it-may flow through line Ll, wire 69, interlock e,'wire62, coil61, wire 60 and line L2 depending'upon the Vpolarity ofthe feed lines. c*y Ilhe circuitjust described keeps the oper# ating coil 61 energizedregardless of the polarity ofv the feed lines and thus insures anuninterrupted movementfof thevpress ram in .a forwarder upward directionuntil the limit switch'rA is automatically opened or the stop switch 82is previously lopened by the operator in case of an emergency.

When a predetermined pressure between the press elements has beenreached and 'the limit switch A automatically Vopened,*as hereinafterexplained, the contactors-will assume an opened position and, as waspreviously stated, both interlocks e and.;e will be opened. `To releasethe pressure andseparate the press elements, the operator presses thebutton to momentarily close the down switch 81. This closes a circuitindicated in light dot and dash lines in Fig. 3 for controlling thereversing switch B. to operate the motor in a reverse direction for theabove purpose. At this time the current will flow, through line L2,wires 60 and 70, operating coil 71, wires 72 and 73, down switch 81,wire 74, limit switch B, wire 75, stop switch 82 and to the line L3through the wires 66 and 67 which are common to both operating circuits.Y

The operating coil 71 thus energized closes the contactor b whichconnects the feed lines with the motor to throw the latter across theline and thus reverse it. As this contactor is closed, its interlock fis closed, and the current may now ilow through line L2, wires 60 and70, coil 71, wire 72, interlock f, wires 78 and 74, limit switch B, wire75, stop switch 82, wires 66 and V67 and line L3, or it may flow throughline L1, wires 76 and 77, interlock f, Wire 72, coil 71, wires 70 and 60and line L2, depending upon the polarity of the feed lines. The circuitjust described keeps the operating coil 71 energized regardless of thepolarity of the feed linesand thus insures an uninterrupted movement ofthe press ram in a reverse direction until stopped by the automaticopening of the limit switch B or the manual opening of the stop switch82.

It will be understood that the up switch 8O and down switchV 81 aremanually operated to start the press in accordance with therequirements, and that the stop switch 82 may also be manually operatedto stop the press at any time in case of emergency. The limit switches Aand B are automatically operated by the moving parts of the press and tothis end each is provided with an operating or trip arm 26 each of whichnormally occupies a position to close its respective switch but which iscapable of operation to open said switch.V The trip arm 26 of the limitswitchB is disposed in the path of movement of a lug 43 adjustablysecured, as by a set screw 44, to a rod 45 projecting upwardly from theram 16, said trip arm being engaged by said lug to open the limit switchB when the ram 16 has descended to its lowermost position determined bythe adjusted position of said lug on the `rod 45. The trip arm 26 ofthelimit switch A is disposed in the path of movement of a projection 46 ona slide 47 Vheld in a clamp 48 carried by one of the posts 18 and isengaged by said projection to open the limit switch A when said postmoves upwardly under the yielding action of the springs 22. The slidel47 is adjust-- ably carried by the clamp l48 and is preferably providedwith a suitable scale 49, whereby the extent .of yielding movement ofthe springs 22, and consequently the pressure upon the work, necessaryto open the limit switch A may be conveniently varied. The trip arm 26of the limit switch A is alsoV operable to open said switch by a slide50 vertically movable in guides 51 on an upright frame member 52 whichsupports the hand control and limit switches, said slide 50 having anangular upper end 53 disposed in the path of movement of thelug 43 andadapted to be engaged thereby upon excessive upward movement of the ram16.

The operation is as follows:

InV Fig. 1 the ram 16 is shown in a midposition in its path of travel.Assuming that the ram is moving upwardly at this time, this movementwill be continued untilthe dies 17 have closed upon the work and have Yexerted thereon a pressure sufiicient to cause the springs 22 to yieldand the posts 18 to move upwardly. movement, and consequently of thepressure 'exerted upon the work, as predetermined by the adjustment ofthe slide 49 in the clamp 48, has been reached, the projection461engages the trip arm 26 of the limit switch A, thereby opening saidswitch and stopping the When the limit of this movement of the ram. Thework is there- Y upon resiliently held under the predetermined pressureby the springs 22 which, in case of any shrinkage of the work, can'expand slightly to exert a follow-up pressure f thereon. To lrelease thepressure and sepavrate the press elements, the down, switch 81 ismomentarily closed, thereby reversing the motor M as above described.The ram 16 is thereupon moved downwardly until'v the lug 43 engages thetrip arm 26 of the limit switch B, opening the latter switch and againstopping the motor M andthe movement of the ram.

In the event of breakage of the springs 22, or stripping of the threads.on` the upper ends 19a of the posts 18, or the failure of the nuts 19,or other condition preventing the bed 15 from exerting its normalreaction to the upward pressure of the ram, the vconsecpient abnormalupward movement of the ram will cause the lug 43 to engage the angularend 53 of the slide 50, thereby opening the limit switch A andautomaticallyv stopping the press.

The armature shaft 42 is preferably provided with a brake 54 normallyapplied by a spring 55 (Fig. 5) but held released against the tensionof'said spring when the motory is running by a solenoid 56 in a shuntcircuitV 57 (Fig. 3) between the feed lines'Ll and L2.

Means are preferably provided forindieating the pressure exerted by thepress upon the work, said means, as shown in Fig. 1, comprising a dialplate secured by a bracket 121 to the upper end of one of thev posts 18and having aA suitable graduated scale. Journalled in the dial plate 120is an arbor 122 carrying at one end a pointer 123` movable over thescale on said dial plate. Secured to the opposite end of the arbor 122is a pinion 124 wliichjcooperat'es'with a rack bar 125 carried bytheframe member 52.` It

- cated' on the dial 120 by the pointer 128 due to the movement ofthe'bracket 121 relative to the frame member 52.

Iclaim:

31. In a press, the combination with relatively movable press elements,of a resilient element associated with one of said press elements andsubjected to the pressure exert'- ed therebetween, means Vfor relativelymoving said elements toward one another, comprising a rack carried byone of said press elements, a train of gearing, and an electric motor,means including an electric circuit for controlling said moving means,and means controlled by the yielding movement of said resilient elementand consequently by the amount of said pressure for controlling saidelectric circuit and thereby stopping thel relativefmovement ofsaidelements when a predetermined pressure has been reached.

. 2. In a press,the combination with relatively movable pressA elements,of an element subjected to the pressure exerted between said presselements and displaceable thereby amounts varying with the amount ofsaid pressure, means Jfor relatively moving said elements toward oneanother, comprising a rack carried by one ot said press elements, a

`train of gearing, and an electric motor, means including` an electriccircuit for controlling said moving means, and means actuated by apredetermined movement of said displaceable element for controlling saidelectric circuit andithereby stopping the relative movement of saidpress elements.

3. In a press, in combination, a resiliently supported bed, a ram, meansfor moving said ram toward and from said bed, comprising a rack carriedby saidram,`a train of gearing, and an .electric motor, means includingan electric circuit for controlling said moving means, and meansoperatively connected with both said ram and said `bed for controllingsaid circuit to stop vthe movement of said ram upon a. predeterminedmovement of either of said elements. y

4. In apress, in combination, a bed, a resilientsupport for said bed, aram,'means' for moving said ram towardsaid bed, comprising a rackcarried by said ram, a train of gearing, andan electric motor, and meanscontrolled by the pressure exerted between said bed-and ram forcontrollinglsaid moving means and for stopping the movement ofsaid ramwhen a Vpredetermined pressure has been reached, said last` namedVmea-ns being also rendered operative to stop said movement uponfailureoi said bed to exert its normal reaction to said pressure. f 5.In a press, in combinatiomaa bed, a resilientsupport for said: bed, aram, means forV the pressure of sai-d ram for controlling said circuittostop said moving means.

6. In a press, in combination, a bed, a resilient support for saidV bed,a ram, means for moving said ram toward said bed, comprisinga rackcarried by said ram, a train of gearing, and an electricmotor, meansincluding an electric circuit for controlling'said.

moving means, and means controlled by the pressure exerted betweensaid'bed and ram for controlling,saidelectric circuit and therebystopping the movement of said ram when a predetermined pressure has beenreached',

said last named means being also rendered operative to stop saidmovement upon failure' of said bed to exert its normal reaction to saidpressure.

7. In a press, in combination, a bed, a resilient support for-said bed,a ram, means including'a rack carried by saidram, a train of gearing-andan electric motor for moving said ram toward said bed, and meansVrendered operative by failure of said bed to exert its normal reactiontov thepressure of 'said ram `i'orbrealiing the circuit to said motor.

8. In a press, in combination, a resiliently su 3 orted bed a ram meansfor movin@ saidram toward said bed, comprising a rack carried by saidram, a tram of gearing, and an electric motor,`means including anelectric circuit forv controlling said moving means, a-

inember movable with said bed, a clamp carried by saidl member, a slideadjustably mounted in said clamp 'and having an'engaging portion, and amember engaged by the engaging portion of said slidewhen said bed yieldsJfor controlling the electric circuit and thereby stoppingthe movementof said ram by said moving means.

9.: In a press, in combination, a resiliently supported bed, a ram,means including a rack carried by said ram, a trainl of gearing, and anelectric motor for moving said ram toward and fromsaid bed, automaticmeans loperatively connected with both said ramand said bed for openingthe circuit to said motor and stopping the movement of said ram upon apredeterminedl movement ram upon a predetermined movement ot said ramtoward and away from said bed, and manually operable means for closingthe circuit to said motor and starting the movement of said ram in theopposite direction upon operation' of said automatic means.

l1. ln a press the combination of a bed, a ram, springs for supportingsaid bed against the pressure of said ram, mechanism for moving said ramtoward and away fromv said bed, comprising a rack carried by said ram, atrain of gearing, an electric motor, different electrical circuits tosaid motor for controlling the movement of said ram in either direction,manually operable switches for completing each of said circuits to movesaid ram in either direction and opening said completed circuit to stopsaid ram at any position, and means tor automatically opening saidcompleted circuit to stop said ram upon a predetermined movement of saidram in either direction.

12. In a press the combination of a bed7 a. ram, springs for supportingsaid bed against the pressure lof said ram, mechanism for moving saidram toward and away from said bed, comprising a rack carried by saidram, a train of gearing, an electric motor, different electricalcircuits to said motor for controlling the movement of said ram ineither direction7 manually operable switches for completing each of saidcircuits to kmove said ram in either direction and opening saidcompleted circuit to stop said ram at any position, a limit switch ineach of said circuits, and a stop device'to control each limit switchVand automatically open said completed circuit and thereby stop said ramupon a predetermined movement of said ram in either direction.

V13. In a press thel combination of a bed, a ram, springs for supportingsaid bed against the pressure of said ram, mechanism for moving said ramtoward and away from said bed, comprisingV a rack carried by'said ram,atrain of gearing, an electric motor, ditlerent electrical circuits tosaid motor for controlling the movementof said ram in either direction,manually operable switches for completing each of said circuits to movesaid ram in either direction'and opening said completed circuit to stopsaid ram at any position, a limit switch in each of said circuits, astop device to control each limit switch and automatically open saidcompleted circuit and thereby stop said ram upon a predeterminedmovement of said ram in either direction, and anauXiliary stop devicerendered operative'by failure of said bed to exert its normal resistanceto the pressure of said ram for controlling its respective limit switchand thereby limit the movement of said ram toward said bed.

ln testimony whereoi1 I aiiiX my signature.

JASPER DERBY.

